NEUTRAL HYDROGEN ABSORPTION IN NGC-1068 AND NGC-3079

Citation
Jf. Gallimore et al., NEUTRAL HYDROGEN ABSORPTION IN NGC-1068 AND NGC-3079, The Astrophysical journal, 422(1), 1994, pp. 120000013-120000016
Citations number
28
Categorie Soggetti
Astronomy & Astrophysics
Journal title
ISSN journal
0004637X
Volume
422
Issue
1
Year of publication
1994
Part
2
Pages
120000013 - 120000016
Database
ISI
SICI code
0004-637X(1994)422:1<120000013:NHAINA>2.0.ZU;2-F
Abstract
We have used the VLA in A configuration to obtain spatially resolved 2 1 cm absorption spectra of NGC 1068 and NGC 3079. The bulk of the abso rbing H I in NGC 1068 appears to be located in the inner disk and is o riented such that the brighter, northeast radio lobe is located in fro nt of the disk and the fainter, southwest radio lobe is located behind . We find evidence for a shock front inside the leading edge of the st ellar bar based on the kinematics and column density distribution of t he H I. Near the radio nucleus of NGC 1068 the H i appears to be parti cipating in a wind-driven outflow. In NGC 3079 we detect slightly reso lved H I absorption against the radio core. This absorption is charact erized by strong, multiple components: (1) broad absorption (FWZI grea ter than or similar to 895 km s-1) with a deep core near the systemic velocity and a slight blue asymmetry, and (2) red- and blueshifted com ponents which are slightly resolved by the VLA beam. These Doppler-shi fted components might arise in a wind-driven outflow or a slightly res olved circumnuclear ring (approximately 90 pc radius). Assuming circul ar orbits, the virial mass interior to the alleged ring would exceed 1 0(8) M..